FCC Technician Exam Question Of The Day (T0A04)

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Q) What is the purpose of a fuse in an electrical circuit?

A) To interrupt power in case of overload

NJ2X Notes:
Fuses play an important role by protecting a circuit from current overload. Fundamentally a fuse is a short length of wire in a glass envelope that will melt at or above a specific current level. The basic idea is to design a circuit so that the fuse will break down before the wires and components are destroyed or catch fire. You want the fuse to be the weakest link in the electrical chain.

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